Dredge having bucket emptying means



Nov'. 4, 1969 H. HEITZER DREDGE HAVING BUCKET EMPTYING MEANS Fiied June v, 196e lNvENToR HEINRICH HE/TZEf United States Patent O 3,475,842 DREDGE HAVING BUCKET EMPTYING MEANS Heinrich Heitzer, Neuss, Rhine, Germany, assignor to Deming-Lauchhammer, Maschinenund Stahlbau GmbH., Dusseldorf-Benrath, Germany Filed .lune 7, 1966, Ser. No. 555,821 Claims priority, application Germany, June 9, 1965,

Inf. c1. Eozf 3/24; Besg 47/40 U.S. Cl. 37-189 5 Claims ABSTRACT F THE DISCLOSURE A dredging device comprises a dredging arm member which carries at its outer end a rotatable bucket wheel. The bucket wheel carries a plurality of buckets having forward opened ends and trailing closed ends. The buckets are pivotally mounted on the bucket wheels by arms which are connected around the forward ends of the buckets and which pivot adjacent the circumference of the Wheels. The trailing bucket ends are connected through spring elements to the Wheel and these spring elements urge the trailing ends inwardly toward the wheel circumference. As the wheel is rotated the trailing ends of the buckets are brought into contact with a lifting cam which strikes against the trailing ends and causes it to move outwardly from the circumference of the wheel to dislodge any material which is carried therein. When the bucket moves beyond the cam again it moves inwardly under the force of its connecting spring back against the wheel, to further loosen any material which may remain in the bucket.

In the dredging of sticky or adhesive material, using bucket wheels, emptying of the buckets presents some difficulties because some dredged materials have a tendency to adhere to the bucket Walls. Such materials are released from the bucket very slowly and only under the inliuence of gravity. If the material falls out too slowly,

the bucket will be moved downwardly for another load when it is only partly empty and instead of the material being delivered to the discharge chute, it will be dropped backwardly down into the formation being dredged.

In order to overcome this disadvantage, different discharge devices have been proposed. In the prior art discharge or emptying devices, the buckets are tiltable or swingable about an axis which extends parallel to the axis of the bucket wheel. The tilting movement is caused by displacing the center of gravity of the filled buckets relative to the empty bucket position, or by means of using a spring, the bucket is tilted into a discharge position which is fixed or determined by an abutment. It has been demonstrated, however, that even with such measures, very sticky material will still not be discharged rapidly enough or in sufficient quantities.

In accordance with the present invention, there is provided a bucket wheel construction in which the buckets are mounted on the wheel so that they are pivotal for the purpose of discharging the contents and in which the buckets are resiliently held in -an operative position against the wheel and with means being provided to effect a lifting force contrary to the spring action to aid in the discharge of the material from the bucket when it is at an appropriate location. In the preferred arrangement, the mechanism includes a ring which is arranged stationarily alongside the bucket wheel ring and provides camming means or roller means which are effective to engage suitable camming or roller means on each bucket when it passes at a selected location. One or more such camming arrangements are advantageously provided in order to effect a lifting action on the trailing end of a Mlce bucket so that its forward end tilts downwardly for discharging the material therein. The camming means may advantageously provide two discharge pushes or strikes by each camming arrangement so that the material may be shaken off the interior walls of the buckets and discharged. During the movement of the buckets, beyond the camming means, the buckets and their contents are subject on the one hand to the mass forces and the spring and gravity force on the other hand. They are subjected to a lifting force which is imparted by the camming means at a location of bucket wheel movement where it is most desirable to dislodge the material from the bucket. The bucket is first lifted by a camming means against the action of the spring to cause an impact and a dislodging effect on the material in the bucket and it is subsequently subjected to a return action by the spring which brings the bucket downwardly against the bucket wheel to cause a further impact and dislodging of the material. Impact rollers are preferably used instead of gliding pieces because the rollers are subject to less wear.

A further feature of the invention is that the apparatus can be adapted to the characteristics of the material to be dredged. For example, when the dredging material has ordinary consistency, the impact producing mechanism may be easily removed from a position at which it will be effective on the buckets at the discharge station. On the other hand, if the goods are very sticky, camming mechanisms which would use a greater lift and impacting force may be employed or a plurality of such mechanisms may be disposed along the path of movement of the buckets to provide for a series of impacts.

Accordingly, it is an object of the invention to provide a dredging device which includes a rotating bucket wheel having a plurality of buckets pivotally mounted thereon adjacent the forward ends of the buckets with spring means holding the trailing ends downwardly onto the wheel and with camming means arranged at a stationary location adjacent the bucket wheel to cause the lifting of each bucket and the pivotal movement thereof about its pivotal mounting and away from the bucket wheel to shake the material out of the buckets as they are advanced beyond a material discharging station.

A further object of the invention is to provide a dredging device which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

In the drawing:

FIG. l is a side elevational view of a dredging device constructed in accordance with the invention;

FIG. 2 is a section taken along the line 2--2 0f FIG. 1; and

FIG. 3 is a section taken along the line 3 3 of FIG. 2.

Referring to the drawing, in particular, the invention embodied therein comprises a dredging device, generally designated 20, which includes a supporting arm and discharge chute member 22 upon the outer end of which a bucket wheel or ring 10 is rotatably mounted. The bucket wheel 10 is privided with a plurality of buckets 24 which are pivotally mounted on an extension arm 26 at a pivot location 5 adjacent the forward opened end of each bucket.

In accordance with the invention, the trailing end of each bucket is provided with a plate portion 24a which includes a portion which is normally urged downwardly against the outer periphery of the wheel 10 by a spring assembly generally designated 6 which is secured to the plate 24a by bolts 28 which extend through a plurality of Washers 29 and an upper plate portion 7 of the spring assembly 6. A slide or cam plate 8 is secured to the underside of plate portion 7. The spring assembly 6 includes a resilient member 6a which is connected to the plate 7 by means of a bolt 32 and a retaining plate 34. The resilient member 6a urges the plate 34, bolt 32 and hence the plate 7 in a downward direction in respect to the periphery of the wheel 10 to cause the cam plate 8 to engage the roller 4 during rotation of the wheel 10.

The invention construction further includes a stationary carrier of wheel member 1 which is mounted at the end of the arm 22 alongside the bucket wheel 10. The stationary carrier 1 and each bucket, in accordance with the invention, is provided with at least one camming mechanism for causing the upward lifting movement of the bucket during its travel around the upper arcuate portion of the stationary carrier 1. In the embodiment illustrated in FIG, l, the camming means includes the roller 4 which is arranged on a stationary carrier and is rotatably mounted in a position to engage the cam plate 8 which is carried on each bucket 24 at the location below the plate 30 of the spring assembly 6. Although the rollers are mounted on the stationary member and the cam plate 8 is carried on the buckets, the operation of the device would be satisfactory if the reverse were true. The rollers are advantageously arranged in a bracket 35 which may be mounted at any desired peripheral location on the carrier 1. The bracket 35 is advantageously provided with a plurality of journal bearing portions for openings 9 for the rotative support of the rollers 4 in any selected location, that is, either the center location which is indicated in the drawings, or either one of the end locations of the bores 9.

The buckets 24 are tiltable against the action of the spring assembly 6 which presses the rear end of the buckets against the bucket ring. The tilting movement is effected about the pivot pins or bolts which are parallel to the rotational axis of the bucket wheel. The cam 8 which is provided to engage the rollers 4 is advantageously selected to provide a quick lifting impact on the trailing end of the buckets and then permit a rapid return of the bucket by the action of the spring 6. The shape and design of the cam 8 may be made in accordance with the desired lifting impact which is to be imparted as well as the desired return impact when the spring causes the buckets 24 to be moved backwardly against the ring 10. For this purpose, the cams 8 are made so that they are interchangeable and cams may be designed, for example, to provide for a series of pushes or impacts for engagement with one or more rollers.

What is claimed is:

1. A dredging device comprising a supporting arm, a

bucket wheel rotatably mounted on said supporting arm, at least one bucket on said bucket Wheel having closed sides a forward opened end and trailing closed end, said bucket being pivotally mounted adjacent its forward end on said Wheel, spring means urging the trailing end of said bucket inwardly toward said bucket wheel, camming means adjacent said wheel along one side of said bucket and exterior of said bucket and engageable with the exterior of said bucket at a spaced location from the forward end of said bucket to effect impact with and lifting of said bucket outwardly against the force of 'said spring means and to cause pivotal movement about its mounting on'said wheel for the purpose of loosening material from said bucket for discharge from the opened forward end thereof and permitting said bucket to move inwardly toward said wheel under the force of said spring means to further loosen the material.

2. A dredging device, according to claim`1, wherein said bucket includes a rear plate portion', said' spring means including a spring assembly mounted on said bucket wheel and connected to' said rear plate portion and urging said plate portion downwardly against the periphery of said bucket wheel, said rear plate portion carrying an exterior cam constituting a portion of said camming means, and a roller mounted adjacent said wheel in the path of movement of said bucket arm and said wheel and located to contact said cam to lift said bucket.

3. A dredging device, according to claim 2, including means for mounting said roller at a plurality of selected locations in respect to the periphery of said carrier.

4. A `dredging device, according to claim 1, wherein said camming means includes a roller, means mounting said roller in a fixed position adjacent said bucket wheel in the path of movement of said bucket, and a cam carried on said bucket adapted to engage said roller.

5. A dredging device, according to claim 4,v including means for adjustably positioning said roller in respect to said carrier.

References Cited UNITED STATES PATENTS 365,580 6/ 1887 Carter 37-94 708,583 9/ 1902 Powell 37-70 857,396 6/ 1907 Hammond 198-144 1,199,366 9/1916 French 37-94 1,301,344 4/1919 Wehner 37-94 1,302,046 4/ 1919 Hunt i 37-190 XR 1,760,964 6/ 1930 Ruth 198-144 ROBERT E. PULFREY, Primary Examiner C, D. CROWDER, Assistant Examiner 

